The method for obtaining the cushioning curves of the packaging materials used to protect products consists of dropping a flat platform with a known mass onto the cushion sample to be tested from a specified height. The peak acceleration value produced during the test is measured by an accelerometer at the top of the platform. By repeating the test with different masses and from different heights, the characteristic curves of the cushioning material tested are obtained.
Current testing machines consist of a guiding plate comprising an anchoring system to raise or lower the load in order to position it at the desired drop height, having a system that releases the platform and an accelerometer that measures the acceleration peak. In addition, a brake actuator is provided that prevents the platform from hitting the cushioning material a second time, once it has rebounded. The drawbacks of such machines include the following:                (a) Although both lightweight and heavyweight platforms can be used to reach lower static loads during testing, the heavyweight platform must be removed to mount the lightweight platform, which is time-consuming.        (b) When using the lightweight platform, the braking and release mechanism is not actuated, and the entire operation has to be performed manually, with the resulting loss of precision in defining the drop height and possibly impacting a second time without being able to stop it by hand.        (c) When using one platform or the other, the drop height is established by using a millimeter ruler. As it is not controlled by a PLC (Programmable Logic Controller), but rather it is the operator who halts the platform at a particular height using the millimeter ruler, the low precision, combined with human error mean the tests are not very reproducible.        
An example of this is the U.S. Patent US20090031783, which describes a resistance test apparatus for packages or other objects that consists of dropping or launching said object vertically downwards and verifying the damage produced. During launching various data are acquired, such as, for example, speed and acceleration.
Another apparatus that is also known is marketed by the company Lansmont in which a package is dropped, wherein the damage is determined. The structure of this apparatus consists of a plate that can slide vertically along a guide. However, in this case the package is arranged at a specified height above the plate, making the plate subsequently lower at a downward acceleration greater than gravity, such that the package drops in a free-fall state.